Safety control system for gas burners employing single point ignition



1954 R. A. WITTMANN 2,670,035

' SAFETY CONTROL SYSTEM FOR GAS BURNERS EMPLOYING SINGLE POINT IGNITION Filed Jan. 17,

-3 Sheets-Sheet l I [rm 19: tar"..-

Rolzerf/l. Miimazm Feb. 23, 1954 Filed Jan. 17, 1947 R. ,A. WlTTMANN 1 2,670,035 SAFETY CONTROL SYSTEM FOR GAS BURNERS EMPLOYING SINGLE POINT IGNITION 3 Sheds-Sheet 2 Feb. 23, 1954 R. A. WITTMANN SAFETY CONTROL SYSTEM FOR GAS BURNERS EMPLOYING SINGLE POINT IGNITION 3 Sheets-Sheet 3 Filed Jan. 17, 1947 40 fawn for:

,Poerf/Z. hla'flma/zrg Patented Feb. 23, 1954 UNITED STATES PATENT OFFIQE SAFETY CONTROL SYSTEML FOR GAS BURN- ERS EMPLOYING SINGLE POINT IGNITION 18 Claims. 1

My invention relates, generally, to single point ignition and safety controls for gas burning systems, and, particularly, for domestic gas ranges employed for cooking food.

The usual form of gas cooking range has a plurality of top gas burners, located on a top surface of the range, and a pilot light therefor, together with one or more gasburners remote from the top burners and located in a compartment :frequently referred to hereinafter as an The oven ibur-ner (or burners) isemployed for baking, roasting and broiling operations. Because the [pilot light in such ranges serves to light only the top burners, it is neces sary to light the oven bumfiriby separate means, .a match usually being employed. This requires the operator to turn on the gas and then to ignite the gas promptly, since, if there is delay in igniting it, an explosive mixture accumulates which may become large enough to explode or to flare out of the oven and :burn theoperator when themixture is ultimately lit.

It is an object of my invention to provide a single point ignition system for a gas range which entirely eliminates the use of matches, or

similar devices, for ignition of oven burners by having theoven burner, as well as the top burners, lit by one constantly burning pilot light, which is remotely located from the oven burner.

Single point ignition, as generally known, comprises means whereby the top burners of a gas range and the oven burner or burners are all lit from one-constantly burning pilot light which is generally. located centrally with respect to the top burners of the gas range. By means 'of flash tubes which are adapted to carry gas from a burner to a pilot light, the oven burners, or a pilot therefor, may be lit directly from the constantly burning pilotlight which usually adjacent the top burners. vA constantly burning pilot light in the oven is not satisfactory, since it produces uneven oven temperature, is uneconomical, and is dangerous if it fails to light or is extinguished, since it will then permitan accumulation of gas within the oven to an explosive degree.

In previous attempts to employ a single point ignition system an automatic temperature responsive gas valve has been employed in the gas supply line of the oven and has had its heat responsive elements adapted to cause opening of 'the valves when the-pilot for the oven burner is lit. However, whenthe oven pilot is turned off, in order that the automatic temperature responsive valves'will close to-cut off the gas iii supply to the main oven burner, there has been a failure to obtain prompt shutting off of the oven burner, since the heat responsive means of the automatic valves is still subject to the high ambient temperature of the oven in which the main oven burner continues to burn. Consequently, the heat responsive means of the automatic valve cools slowly and the mainoven burner-is notshut off for some littletime.

It is an object of my invention to provide a single point ignition-system for top burners and an oven burner, wherein the-oven burner is controlled by a single manually operated onoff" valve, the oven burner lighting automatically in less than seconds when the valve is turned to its on position and being instantaneously shut olf when said manually controlled valve is turned to its oif position.

In the accomplishment of the foregoing object *1 employ with the manually controlled valve an automatic heat responsive valve which may be positioned either in or out of the ambient temperature of the oven and the oven burner, but which'is responsive tosaid oven pilotburner.

The automatic heat responsive valve controls the'flow of gas to the oven burner and to an auxiliary pilot for the oven burner when the manually operated valve is turned to its on position. This automatic valve will not open to "permit the flow of gas to the oven burner and auxiliary pilot until the oven pilot has been lit from the constantly burning top burnertpilot light. Instantaneous shutting off of the flow of gas to the oven burner and to the pilot for the oven burner is accomplished by turning of vthe manually controlled valve to its 01f posiin the .oven protects the user of the gas range who shuts on the gas to the oven burner and then decides almost immediately thereafter to turnthesameon again. When the automatic valve -;does close, it closes thepassageway to the main, oven burner andit shuts off the-flow-ofgas tothe auxiliary pilot which is then no longer requiredto remain lit for protective purposes.

In .-order; to make said automatic heat responsive valve close :more quickly following manipulation of the manually controlled valve to ofi-iposition,iirso construct-the automaticxvalve the automatic heat responsive valve closes.

which are very important, the automatic valve provides the further very important advantage,

namely, that no unburned gas can accumulate in the oven, even in case of failure of the automatic heat responsive valve itself, whether the failure occurs when the valve is in open position or closed position, due to dirt, corrosion, mal adjustment, etc. If the valve fails to respond when it is in closed position, no gas can flow to the main oven burner or to the auxiliary oven pilot and consequently only the oven pilot itself will burn. There will be no unburned gases of any sort in the oven. If, on the other hand, the automatic heat responsive valve fails when it is in an open position and the operator shuts off the manually controlled valve and thereby closes off the flow of gas to the oven burner and the oven pilot, the only gas which will continue to flow through the automatic heat responsive valve will be to the auxiliary pilot which is lit. Consequently, there can be no accumulation of unburned gases in the oven even when the automatic valve fails in its open position.

Since the rate of flame propagation varies with different gases, it is sometimes desirable to employ an intermediate pilot in combination with the flash tube from the constantly burning pilot light to the oven pilot. It would be unecoresponsive valve which controls the flow of gas to the main oven burner. Therefore, when gas of a lower flame propagation rate is employed in my single point ignition system my automatic heat responsive valve permits thefiow of gas to said intermediate pilot only after the manually controlled valve is moved to on position and only until the automatic valve permits the flow of gas to the main oven burner.

The automatic heat responsive valve for the oven burner, in its preferred form, relies upon the magnetic character of Curie point metals, namely, metals and alloys which normally are ferromagnetic but which, when heated sufiiciently, lose their magnetic properties. The transition temperature, or Curie point as it is called, at which this change in magnetic characteristics occurs on heating is a, distinct property of each metal or alloy and varies widely among the various metals and alloys. Each metal or alloy, however, has its own distinct and nonvarying Curie point. A valve member moved in response to the attraction between a magnet and a Curie point metal may, therefore, be manipulated by heating of the Curie point metal above its Curie point. Since the means, for transmitting heat from a burner-to-be-controlled to the Curie point metal, is positioned in the vicinity of said burner, it has been difficult in prior systems to cause prompt closing action of valve member when the manually controlled pilot valve is moved to off position, since the ambient temperature does not change because the main source of heat continues to operate. Although I prefer to employ a heat responsive valve such as above described, valves controlled by gas filled bellows, bi-metal thermostats, thermocouples or other known heat responsive controls come within the scope of my invention.

It is an object of my invention to provide means whereby the Curie point metal may be cooled rapidly'below its Curie point, so that the valve member responsive to the attractive force between the Curie point metal and the other magnetic member. may be operated quickly. In

the accomplishment of this object I provide a valve in which the Curie point metal is positioned directly in the flow of the gas which is directed to the burner to be controlled and permit a restricted flow of said gas to a small auxiliary jet after the main burner to be controlled has been instantaneously shut off. When the Curie point metal is cooled below its Curie point with the assistance of said cooling iiow of gas, the restricted flow of gas is also shut off by operation of the automatic valve. A very definite snap action of the valve is obtained by using a Curie point metal and permanent magnet. Such metals retain their temperature responsive characteristics indefinitely.

It is a further object to provide a safety control valve for the constantly burning pilot light of the single point ignition system, so that all flow of gas to the top burner or oven burners will be stopped when said pilot light is extinguished accidentally, or otherwise. In this way gas cannot flow from the top burners to the room or from the oven burner to the oven, even when the control valves for said burners are turned to on position, either accidentally or intentionally.

Other objects, uses and advantages of my invention will become apparent from the following description when taken with the accompanying drawings, in which:

Figure 1 is a diagrammatic plan view showing a gas burning system employing my invention;

Figure 2 is a diagrammatic elevational view taken on the line 2-2 of Figure 1;

Figure 3 is an enlarged elevational view taken on the line 33 of Figure l;

Figure 4 is an enlarged elevational view taken on the line 4-4 of Figure 1;

Figure 5 is a fragmentary view, partially in section, illustrating the on" position of the manually controlled valve of Figure 1; I

Figure 6 illustrates a modified form of the automatic heat responsive control valve shown in Figure l; and

Figure 7 illustrates another modification of the automatic heat responsive control valve of Figure 1.

Like reference numerals have been employed in the several views to indicate the same or similar elements.

Referring now to Figures 1 through 5, the reference numeral it indicates an inlet or supply conduit through whichgas enters the gas burning system. In series with the pipe it is an automatic safety shutoff valve, indicated generally by the reference numeral 12, which is open when the pilot light I3 at gas jet or nozzle M is lit, and which is closed when said pilot light is extinguished for any reason. Pilot light 53 is intended to be constantly burning and is hereina'fter referred toasa constantly burning pilot light or constant pilot burner. A heat conductor l extends from the valve I2 to the flame I3 at the nozzle [4 and serves with other control mechanism in the valve l2 to shut off the valve when the pilot light 43 is extinguished. Fordetails of such a valve, reference may be made to my'Patent No. 2,233,659, dated March 4, 1941. The gas jet l4 communicates with valve I2 by pipe l6. When the pilot light [3 is extinguished and the valve 12 closes, no gas will be supplied to conduits beyond the valve, for example, conduits l8 and 44. Conduit l8 connects the'discharge side of valve l2 with the gas manifold 20 bya T-joint 22. The top burners 24 of the gas burning system are connected in parallel with the'manifold 20 through their respective valves 26 and conduits 28. Flash tubes 30 lead from each of the top burners 24 to the pilot light [3, so that when the valve 26 of any top burner is opened, gas will flow from the manifold 20 through the valve 26 and conduit 28 to the burner 24, and gas escaping therefrom will flow upwardly through its flash tube 35 to the pilot light l3 at nozzle 14 and thereby become ignited, the flame flashing back from the pilot light l3 to the top' burner 24 to light said burner.

A conduit 32 leads from the inlet conduit It, in advance of valve l2, to an automatic heat responsive valve, indicated generally by the reference numeral 34, and communicates with the inlet chamber 36 thereof. In Figure 1 the valve 34 hasbeen turned from its normal position, wherein the valve stem 18 extends vertically, in order that the sectional'view thereof may better show the valves internal structure. A valve seat 38 in chamber 35 communicates with a conduit 46 which interconnects chamber 36 with a manually actuated oven burner control valve, indicated generally by the reference numeral 42. If desired,-the operating handle 4! for valve 42 may also actuate the usual thermostatic control for the oven. Valve 42 is an on-oif valve, having three ports 43a, 43band 430. As will be noted hereinafter, in some installations the valve will needonly 2 ports, port 430, together with conduits 46 and 60 then being omitted. A passageway 44 leads from the conduit [8 on the discharge side of the valve l2, to said manually controlled valve 42. When valve 42 is turned to on position, port 43a thereof interconnects passageways 44 and 66.

The inlet chamber 36 of automatic valve 34 is separated from the outlet chamber 46 by wall structure 46 and 48a which will be referred to more fully hereinafter. A conduit 50 leads from the outlet chamber 46 of the automatic valve 34 to a T-junction with a conduit 52, having at one end an auxiliary pilot (sometimes referred to as an auxiliary pilot burner) 54 adjacent the oven burner 56 and, at its other end, being in series with the manually actuated oven burner control valve 42.

When the manually controlled valve 42 is moved to its on position, as illustrated in Figure 5, conduit 52 is interconnected by port43b with a conduit 58 which connects with the oven burner 56, andconduit 40 is connected byport 430 with a conduit 60 which leads to an intermediate pilot (sometimes referred to as an intermediate pilot burner) 62 of the flashtube system or apparatus, which apparatus is indicated generally by the reference numeral 64. At this time, the conduit 44 connectingwith conduit I8 isinterconnected by port 43a with a conduit at which leads to a pilot, or pilot burner, 68 for the oven burner 56. The flash tube system 64 leading'from' the constantly burning pilot light l3 to the pilot 68 for the oven burner 56 has, at an intermediate point, an opening 16 (see Figure 4) above the intermediate pilot 52 which is con nected byconduits 60, 46 and 32 with the inlet conduit I0 when the manually controlled valve 42 is in"on position. Intermediate pilot 52 may be omitted if desired, but with certain types of gas I prefer to employ it to assist flame propagation in the flash tube system 64.

Referring now to the automatic heat responsive valve 34, it will be seen that the inlet chamber 36 is separated from the outlet chamber 46 by walls 46 and 48, a passageway '12 being formed in the former wall and having a valve seat T3 at one end. The passageway i2 may be closed by a valve member 14, and conduit 46 may be closed by a valve member 76, both members 14 and 16 being fixedlysecured upon the same rod 16 which is guided by passageway 86 in the wall 46a. A spring 82 is interposed between the wall section 481i and the valve member l4, thus assisting gravity to urge the valve members l4 and I6 downwardly, as viewed in Figure 1, and away from the valve seat '13 and toward the seat 38. At the upper end of the rod 18 is fixed a permanent magnet 84 which is attracted toward a piece of ferromagnetic Curie point metal 86 when said metal 86 is at a temperature below its Curie point.

. This Curie point metal 86 is supported by a heat conducting member 68 having. apertures 82% around the metal 66. The member 88 extends out of the housing of the valve 34 from between the casing 96 and the lid 92 into the vicinity of the oven burner pilot 68 and the oven burner 55. When the pilot 63 is lit, heat is transferred through the conducting member 88 to the Curie point metal 8% which, because of such heating, loses its magnetic qualities and fails to exert an attractive force on the permanent magnet 84 when a temperature above its Curie 'point is reached. Thereupon, the spring 82, together with the force of gravity, forces the valve members '14 and I6 downwardly, as viewed in Figure 1. This results in the valve member 14 being unseated and in the valve member 16 being seated upon the seat 38.

At this time, there is a means of communication between the inlet chamber 36 of the automatic valve 34 and its outlet chamber 46, and gas under pressure will therefore flow from conduit l0 through conduit 32 into chamber 36. From chamber 36 the gas will flow through the passageway 12 and be directed by wall sections 48 and 48a, all about the Curie point metal 86 which is directly in the path of the flow of gas to the outlet chamber 46 and to the conduit 50, with a resulting cooling action on said Curie point metal. When the oven burner pilot 68, or the oven burner 56, is lit any flow of gas past the Curie point metal 56 will fail to bring said metal below its Curie point. However, continued flow of gas past the metal after the pilot 68 and oven burner 56 are extinguished will assist in cooling the Curie point metal 86 and the heat conducting strip 88, so that the Curie point metal 86 will more quickly reach a temperature below its Curie point and thus regain its magnetic qualities for purposes of attracting the magnet 84 and thus closing the passageway 12 to prevent further flow 'of gas through the automatic valve to the a outlet'chamber 46 and thence to the oven burner 56 and auxiliary oven pilot 54.

The operation of my gas burning system will now be described. Assuming that the pilot light 53 is lit, so that the valve l2 will be in open position, gas will flow into conduit l8 and from there to gas manifold 29 and the valves 26. Simultaneously, gas will flow to the conduit 44 from conduit l8 and then to the manual controlled valve :52 which is in blocking or off position. No gas will flow from the manifold to the top burners 24 unless the individual valves 28 of these burners are turned on. If, for any reason, the pilot light it is extinguished, safety valve l2 will close and no gas will be supplied to conduit it or other conduits beyond the valve l2. With the oven burner 5?; turned ofi and the Curie point metal 86 of valve 34 at a temperature below its Curie point, the valve member 14 of automatic valve 35 will be seated and the valve member 16 of said valve t l will be unseated, thus permitting a flow of gas from the inlet chamber 35 of valve 36 to the conduit til, and from there to the manually controlled valve t2 which, at this time, blocks the flow of the gas from conduit 40 to conduit 60.

When it is desired to light the oven burner, the operator merely turns the manually operated oven burner control valve 42 to its unbloclaing or on position, such as that illustrated in Figure 5, whereupon pairs of conduits and 58, it and 65, and l5 and 59 will be interconnected by the ports of valve 52. This will permit the iiow of gas from the inlet chamber of valve 3d through the conduit it and conduit 53 to the intermediate pilot E2 of the flash tube system 95 and, simultaneously, will permit the flow of gas from the conduit it through conduit i l and conduit G5 to the oven burner pilot i323. Pilots 52 and 83 will, therefore, supply gas to the hash tube system 5t, said gas flowing from each pilot to the pilot light it at nozzle l i adjacent the top burners 2 3 where the gas is ignited and said ignited gas flashes back and lights the intermediate pilot $2 and also the pilot 58 for the oven burner 55.

Although manipulation of the manually controlled valve 42 to its on position interconnects the passageways 58 and t2, there will be no flow of gas therethrough until gas is supplied through the automatic heat responsive valve 35 to conduit r 51 which is conn cted to the outlet chamber 66 of said valve. This flow of gas will be permitted only when the valve member i l of the automatic valve unseated. Said valve member it will be unseated when the Curie point metal is heated above its Curie point temperature by the pilot {53 and therefore ceases to attract the permanent magnet 34, whereupon gravity, aided by the spring 82, retracts the magnet 8t and the valve member 14 and, simultaneously, seats the valve member 76 upon valve seat 38, thus closing off the flow of gas to the conduit Alli and to the intermediate pilot 62 for the flash tube system 5 Heat for raising the temperature of the Curie point metal 85 above its Curie point is supplied from the oven burner pilot 63 through the medium of the heat transmitting member 88, which is located adjacent the pilot '58 and the oven burner 55. If desired, the heat transmitting member 3!? may itself be formed of Curie point metal.

With the manually controlled oven burner valve :22 in its on position, pilot 68 for the oven burner will become lit, as above described, and upon its heating the Curie point metal as above its Curie point temperature, valve member 14 will be unseated and gas will flow through the automatic valve 34 and conduit 50 to the conduits 52 and 58, thus supplying gas to the oven burner 56 and the auxiliary pilot 5B. As soon as gas is supplied thereto the burner 56 and pilot 54 are ignited from the oven burner pilot 68.

When the operator desires to shut off the oven burner, he turns the manually controlled valve to oil position, whereupon conduit 58 leading to the oven burner 56 is immediately disconnected from its source of gas from conduit 52 and the oven burner 55 is immediately extinguished. However, gas will continue to fiow to the auxiliary pilot 54 adjacent the oven burner 56, since the pilot is fed by conduits 52 and 50 from the outlet chamber 45 of the automatic valve 34 which has not as yet closed. Simultaneously, with the shutting on of the gas to the oven arner 55, the gas will also be shut off to the oven pilot 68 by reason of conduit 66 being disconnected from conduit M at the manually controlled valve 2. This means that the only flame which continues to burn, in addition to the constantly burning pilot light It adjacent the top burners 24, is that of the auxiliary pilot 54 which is remote from the heat transmitting member 88 of the automatic valve 3i. Although the ambient temperature surrounding the heat transmitting member 853 at its outermost end may be as high as 650-750 when the oven burner 56 is lit, instantaneous shutting off of burner 56 reduces the ambient temperature, and the heat of member 38 and the Curie point metal 55 is transmitted to the gas which continues to flow through the automatic valve 34 and around the transmitting member 89 and the Curie point metal 86 to the auxiliary jet 5t. Such flow of gas helps to cool the Curie point metal 86 below its Curie point temperature, whereupon the metal rapidly regains its magnetic properties and attracts the permanent magnet 84 which is connected to the rod 13. Rod 78, which carries the valve members 5 3 and 16, thereupon moves upwardly, as viewed in Figure 1, and seats the valve member 14 on the seat 73 and unseats the valve member 16 from seat 38. At this time, the flow of gas from the outlet chamber 66 of valve 34 to the conduit 50 will stop, since the valve member 14 is seated and, consequently, the flame at the auxiliary pilot 54 will go out. Although valve member is has become unseated from seat 38, the flow of gas through the inlet chamber 38 and the conduit 40 is prevented by reason of the manually controlled valve t2 blocking the connection between conduit 9 and conduit fill which leads to the intermediate pilot 52 of the flash tube system 64. At this time, a complete cycle of operation has been completed and the system is in the condition in which it was found prior to the movement of the manually controlled valve 42 to "on position. It will be particularly noted that there is absolutely no time la or delay in shutting off the oven burner. 56, and that such shutting elf is accomplished instantaneously by turning the manually controlled valve is to its off position. In gas burning ranges which do not immediately shut off the oven burner when the manually controlled valve is moved to oil position, the control means of the automatic heat responsive valve continues in a high ambient and cools slowly.

If the'user of the oven shuts off the oven burner and then changes his mind and immediately turns it on again, the auxiliary pilot 54, which continues to burn adjacent the oven burner until automatic heat responsive valve- 34 closes, will nite the gas delivered from the oven burner and thereby prevent the accumulation of an explosive mixture in the oven. However, as soon as the automatic valve 34 closes, turning the manually controlled valve to on position will be inefiective to cause a flow of gas from the oven burner 56 until the pilot light 68 therefor is lit and heats the control means of the automatic heat responsive valve 3s above its Curie point temperature to cause unseating of valve member 14.

Since the top burners and oven burners are all dependent for operation upon the single constantly burning pilot light is adjacent the top burners 24, it is desirable to have a safety shutofl valve, such as valve l2, which is responsive to the presence of a flame at the pilot I3. In this connection, although I have illustrated conduit 32 as being positioned in advance of the valve I2, it will be understood that it may also be positioned on the discharge side of said valve, if that is desired.

In the operation of my single point ignition system it should be further understood that the automatic heat responsive valve need not be identical with valve 34 but may take the form of any one of a number of known heat responsive valves. By way of example, reference may be had to Figure '7 which illustrates another form of heat responsive valve 34', wherein the pilot 68 for the oven burner 56 may act upon a bimetallic strip 94, which in turn is connected with a rod (8 on which are carried valve members it and 1B. When the bimetallic strip M is cold it takes the position indicated by the dotted lines in Figure 7. However, as it becomes heated by the flame of pilot 68, it moves downwardly and opens valve 14 while closing ofl conduit 49 by seating the valve member '16 on the seat 38. When the oven burner pilot 68 is turned off, the bimetallic strip 9 cools and moves toward its dotted line position, thereby seating valve member M and unseating the valve member 16. A flexible diaphragm efi'secured to the rod I8 prevents the escape of gas from the outlet chamber 46 of the valve 3d, while yet permitting upward and downward movement of rod 18.

A modification of the automatic control valve 34 of Figure 1 is shown in Figure 6, wherein it is indicated generally by the reference numeral 34. The only substantial difference between the valve its and the valve 35 of Figure l is in the Curie point metal element I86 which serves both as a magnetic member and as a heat transmitting member, comparable to member @801" Figure 1. The outermost end it? of element I86 is subjected to the flame of the oven burnerpilot 68 and a depressed portion l89 serves as'a magnetic element directly above the permanent magnet 84.

It will also be observed that the element I86 forms the closure member for the top of the valve I34 and therefore eliminates the need of a lid, such as lid 92 of valve 34 in Figure 1. By combining three functions as it does, the element l85 makes the valve te l less expensive than the valve 35.

In this structure, the'flow of gas through the valve *can be directed by the wall structures 48 and lBa the valve 13-4 need not be located immediately adjacent the oven burner which it controls.

Although I have described preferre'dembodiments of myinvention, it will be apparent that modifications may be made therein without departing from the scope of the invention, and that the automatic heat responsive valve may find additional applications other than in my gas burning system.

I claim:

1. For use in a gas burning system having a source of gas, a gas burner, gas ignition means, and gas conduit means adapted to be interconnected between the source of gas and the gas burner, the combination of a pilot burner and an auxiliary pilot burner for said gas burner; manually controlled valve means adapted to block and unblock the flow of gas in said conduits to the gas burner and said pilot burner; means for lighting from said ignition means the gas which is delivered to said pilot burner; automatic valve means adapted automatically to block and unblock the flow of gas in said conduits to the gas burner and said auxiliary pilot burner; control means adapted automatically to eflectthe blocking and unblocking action of said automatic valve means in response to the temperature of said control means, said control means being adapted to be heated by said pilot burner when the latter is lit; said gas burner being adapted to be lighted by moving the. manually controlled valve means to unblocking position whereby gas is supplied to the pilot burner, thereby igniting said pilot burner from said ignition means and heating the control means by said pilot burner to a temperature at which the control means efiects actuation of the automatic valve means to unblocking position for delivering gas to the auxiliary pilot burner and to the gas burner, the gas issuing therefrom being lit from the pilot burner; and the gas burner and pilot burner being adapted to be shut off by movement of the manually controlled. valve means to blocking position, whereupon the control means is no longer heated by the'pilot burner, said auxiliary pilot burner con- .tinuing to be lit until the temperature of'said control means is reduced to a predetermined point whereupon the automatic valve means moves to block the flow of gas to said auxiliary pilot burner.

2. The combination of claim 1 wherein a portion of the control means for the automatic valve means is'disposed in the path of the gas flowing to said auxiliary pilot burner, whereby the control means may be rapidly cooled after said pilot burner for the oven is extinguished by moving the manually controlled valve means to block the flow of gas to said pilot burner.

3. The combination of claim 1 wherein the means for lighting gas delivered to said pilot burner includes a flash tube system which is adapted to extend between the ignition means, in the form of a constantly burning pilot burner, and said pilot burner for the gas burner.

4. The combination of claim 3 wherein the means for lighting gas delivered to said pilot burner includes an intermediate pilot burner for the flash tube system, which intermediate pilot burner is adapted to be connected with the source of gas in series through said manually controlled valve means and said automatic valve means, said automatic valve means being adapted to unblock the flow of gas to said intermediate pilot burner when it blocks the flow of gas to said auxiliary pilot burner and the gas burner, and being adapted to block the flow of gas to said intermediate pilot burner after it has unblocked the flow of gas to said auxiliary pilot burner.

5. For use in a gas burning system, in combination, gas ignition means; a gas burner; a pilot burner and an auxiliary pilot burner for said gas burner; gas conduit means adapted to be interconnected between a source of gas and said gas burner, said pilot burner and said auxiliary pilot burner; manually controlled valve means adapted to block and unblock the flow of as in said conduits to said gas burner and pilot burner; automatic valve means adapted automatically to block and unblock the flow of gas in said conduits to said gas burner and said auxiliary pilot burner; control means adapted automatically to efiect the blocking and unblocking action of said automatic valve means in response to the temperature of said control means, said control means being adapted to be heated by said pilot burner when the latter is lit; said gas burner being adapted to be lighted by moving the manually controlled valve means to unblocking position whereby gas is supplied to the pilot burner, thereby igniting said pilot burner from said ignition means and heating the control means by said pilot burner to a temperature at which the control means effects actuation of the automatic valve means to unblocking position for delivering gas to the auxiliary pilot burner and to the gas burner, the gas issuing therefrom being lit from the pilot burner; and said gas burner and pilot burner being adapted to be shut oil by movement of the manually controlled valve means to blocking position, whereupon the control means is no longer heated by the pilot burner, said auxiliary pilot burner continuing to be lit until the temperature of said control means is reduced to a predetermined point whereupon the automatic valve means moves to block the flow of to said auxiliary pilot burner.

6. For use in a gas range provided with a gas supply pipe, top burn rs, and a single constantly open when said thermally responsive control means is heated above a predetermined temperature by said oven pilot burner when the latter is lit, flash tube means adapted to extend from the constantly burning pilot light to the oven pilot burner to ignite gas at the latter, a second gas supply conduit adapted to interconnect said oven pilot burner with said gas supply, and manually operable valve means disposed in the first conduit between the automatic valve means and the oven burner and disposed in the second conduit between the gas supply and the oven pilot burner for opening said conduits or for closing them.

7. For use in a gas range having a source of gas, an oven burner, and a constant pilot burner, with the oven burner being remote from the constant pilot burner, the combination of a pilot burner and an auxiliary pilot burner for said oven burner, means for igniting said pilot burner from said constant pilot burner when gas is delivered to said pilot burner, gas conduit means adapted to be connected between a source of gas and pilot burner and including a multi-port manually controlled valve means, conduit means adapted to be connected between a source of gas and said oven burner and including said manually controlled valve means and automatic valve means in series, and conduit means connected between the outlet of said automatic valve means and said auxiliary pilot burner, said manually controlled valve means in closed and open positions simultaneously closing off or opening, respectively, said first two mentioned conduit means, said automatic valve means having automatic control means which is responsive to heat produced by the flame oi the pilot burner for the oven burner, with said control means automatically causing said automatic valve means to open when the control means is heated to a predetermined temperature whereby, when the manually controlled valve is in open position, gas may be delivered to the oven burner and said auxiliary pilot burner and is lit from the oven pilot burner, said auxiliary pilot burner continuing to remain lit until the automatic valve means is closed in response to its control means being cooled below said predetermined temperature.

8. For use in a gas range having a gas supply and a constantly burning pilot light, and an oven burner remote from the constantly burning pilot light, the combination of a pilot burner and an auxiliary pilot burner for said oven burner, means including a flash tube and an intermediate pilot burner for igniting said pilot burner from said constantly burning pilot light, manually controlled triple-port valve means, an automatic two-way valve means, a first conduit including said manually controlled valve means adapted to interconnect the gas supply and said oven pilot 7 burner, a second conduit including said manually controlled valve and said automatic valve in series adapted to interconnect the gas supply and said oven burner, a third conduit between the inlet side of said automatic valve means and said intermediate pilot and including said manually controlled valve means in series in said conduit, and a fourth conduit extending between the outlet of said automatic valve means and said auxiliary pilot burner, said manually controlled valve in closed and opened positions simultaneously closing off or opening, respectively, the first three mentioned conduits and said automatic valve means having control means responsive to heat generated by said oven pilot burner and being biased to close ofi said second and fourth conduits and to open said third conduit when said control means is below a predetermined temperature, the cycle of operation for lighting said oven burner requiring movement of said manually controlled valve means to its on position whereby gas is supplied from the inlet side of the automatic valve means to said intermediate pilot and from the source of gas to said oven pilot burner, said last two named pilot burners being then lit from said constantly burning pilot light, said oven pilot burner then heating the control means of the automatic valve means above the predetermined temperature to cause said valve to open the second and fourth conduits, whereby gas is supplied to the oven burner and to the auxiliary pilot burner and is there ignited by said oven pilot burner, and to close oi the flow of gas through said third conduit, and the cycle of operation for closing off said oven burner requiring only a movement of the manually controlled valve to ofi position whereby the flow of gas to said oven burner and oven pilot burner is immediately shut off, said auxiliary pilot burner remaining lit until the control means for the automatic valve means has been cooled below said predetermined temperature whereupon the automatic valve means closes and blocks said fourth conduit and opens said third conduit.

9. The combination of claim 8' wherein the control means for the automatic valve means is positioned in part directly in the flow of gas to the gas burner and to the auxiliary pilot burner whereby the cooling effect of the flow of gas serves more quickly to lower the temperature of the control means below said predetermined temperature when the manually controlled valve is moved to ofi position.

10. For use in a gas burning system having a source of gas, a gas burner, and ignition means remote from said gas burner, the combination of a pilot burner, conduits adapted to interconnect said pilot burner and said gas burner with a source of gas, a two-part valve having one port in the conduit to the pilot burner and the other port in the conduit to the gas burner and effective simultaneously to open or close both con duits, with the flow of gas to said pilot burner being under the control solely of said one port of said two-port valve, automatic valve means positioned in series with that port of the two-port valve which communicates with the gas burner, said pilot burner being adapted to be supplied with gas and being lit by the ignition means when the two-port valve is moved to on position, control means responsive to the heat of said pilot burner for opening the automatic valve means whereby the gas burner will be supplied with gas and will be lit by said pilot burner, an auxiliary pilot burner adapted to be supplied with gas from a source of gas when the automatic valve means opens, the gas from said auxiliary pilot burner being lit from the pilot burner, said gas burner and pilot burner being instantly shutoff when the two-port valveis moved to foif position and said heat responsive control means then being cooled to cause closing of the automatic "valve means to shut off the flow of gas to said auxiliary pilot burner.

11. In a gas range, in combination, a gas supply pipe, a constantly burning pilot light, a safety valve in series in said supply pipe and adapted to close when said pilot light is extinguisheda plurality of top burners connected with the supply pipe on'the discharge side of said safety valve,

individual control valves for each of said top burners, an oven burner remote from the constantly burning pilot light, an oven pilot burner for said oven burner, flash tube means leading from the even. pilot burner to said constantly burning pilot, a conduit leading from the supply pipe on the inlet side of said safety valve to the oven burner, a conduit leading from the supply pipe on the discharge side of said safety valve to the oven pilot burner, manually controlled valve means in both conduits, automatic valve means in series with the manually controlled valve means in the conduit leading tothe oven burner, control means for said automatic valve means adapted to open the latter in response to heat above a predetermined temperature supplied bythe oven pilot burner when lit, a conduit leading from the discharge side of the automatic valve means to an auxiliary pilot burner adjacent the oven burner, the lighting of the oven burner being eifected by moving the manually controlled valve means to open position so that gas may flow to the oven pilot burner and be lit from the constantly burning pilot light, whereupon heat above said predetermined temperature supplied by the oven pilot burner will cause the automatic heat responsive valve means to open and supplygas to the oven burner and auxiliary pilot burner where it will be lit by the oven pilot burner, and the shutting off of the oven burner and oven pilot burner being effected instantly by moving the manually controlled valve to closed position, whereupon the how of gas will continue only to the auxiliary pilot burner until the automatic heat responsive valve means cools below the predetermined temperature and closes.

12. For use in a gas burning system having a gas supply, gas ignition means, and a gas burner remote from the ignition means, the combination of a pilot burner; an auxiliary pilot burner for the gas burner; conduit means adapted tointere connect said gas supply with the gas burner, the pilot burner and the auxiliary pilot burner; means for lighting the pilot burner from the gas ignition means; manually controlled valve means adapted tobe interposed between the gas supply and said gas burner and said pilot burner for blocking and unblocking the flow of gas thereto; automatic valve means for automatically blocking and unblocking the flow of gas in saidconduit means to said auxiliary pilot burner and to said gas burner; heat responsive control means for said automatic valve means adapted automatically to control the blocking and unblocking action of said automatic valve means in response to the temperature of said control means; said control means being adapted to be heated from burning gas at the pilot burner; said gas burner being adapted to be lit by moving the manually controlled valve means to unblocking position, whereby gas is supplied to the pilot burner, igniting said pilot burner from said ignition means by said means for lighting, and heat.- ing the control means to a temperature at which the automatic valve means is automatically moved to unblocking position, whereupon gas will be supplied to said gas burner and to said auxiliary pilot burner, the gas being adapted to be lit from said pilot burner; said gas burner and said pilot burner being adapted to be immediately shut oif by moving the manually controlled valve means to blocking position, said auxiliary pilot burner at that time continuing to remain lit until the heat responsive control means cools below a pre determined temperature.

13. The combination of claim 12 wherein the auxiliary pilot burner is so positioned that, when lit, it does not heat the heat responsivecontrol said first pilot burner, a safety shutoif valve in the fuel supply line for the main burner and operable to closed position to shut off the supply of fuel to said main burner, valve means in the fuel supply line for said first pilot burner and operable to closed position when said safety shutoif valve in the fuel supply line for the main burner is open, whereby to shut off the supply of fuel to said first pilot burner, the combination with said system of stand-by pilot burner means in juxtaposition to the main burner for relighting said main burner when the safety shutoff valve in the fuel supply line to the main burner is in open position and the valve means in the fuel supply line for said first pilot burner is closed, and said pilot burner means comprising a second pilot burner in addition to said first pilot burner, and a fuel supply line for said second pilot burner, and additional valve means partially in the fuel supply line for the main burner and partially in the fuel supply line for one of the pilot burners, said additional valve means being operable to closed position simultaneously to shut off the supply of fuel to both the main burner and one of said pilot burners and to open position simultaneousiy to establish a supply of fuel to said main burner and to one of said pilot burners.

16. In a burner control system of the class wherein there is a main burner, pilot burner means for lighting said main burner, said pilot burner means comprising a first pilot burner, a fuel supply line for supplying fuel to said main burner, a fuel supply line for supplying fuel to said first pilot burner, a safety shutofi valve in the fuel supply line for the main burner and operable to closed position to shut off the supply of fuel to said main burner, valve means in the fuel supply line for said first pilot burner and operable to closed position when said safety shutoff valve in the fuel supply line for the main burner is open, whereby to shut of: the supply of fuel to said first pilot burner, the combination with said system of stand-by pilot burner means in juxtaposition to the main burner for relighting said main burner when the safety shutoff valve in the fuel supply line to the main burner is in open position and the valve means in the fuel supply line for said first pilot burner is closed, and said pilot burner means comprising a second pilot burner and fuel supply means therefor in addition to said first pilot burner, said safety shutofi valve in the fuel supply line for the main burner being under the control of heat responsive means subject to the heat of said second pilot burner, and there being a thermostat controlled valve and a connected gas cook for controlling the supply of fuel to the main burner and to said first and second pilot burners.

17. In apparatus of the class described, in combination, a main burner, a fuel supply line for supplying fuel to said main burner, a first pilot U burner, a safety shutoff valve in the fuel supply line for said main burner, said safety shutoff valve having a fuel inlet and a fuel outlet, heat iii responsive means subject to the heat of said first pilot burner and operable to maintain said safety shutoff valve open when said first pilot burner is ignited and to release said safety shutofi valve for operation to closed position when said first pilot burner is extinguished, a second stand-by pilot burner in juxtaposition to said main burner, and a fuel supply line for maintaining a supply of fuel to said second stand-by pilot burner from the fuel outlet of the safety shutoff valve in the fuel supply line for the main burner, whereby to maintain said second stand-by pilot burner ignited if said safety shutoff valve remains open after said first pilot burner is extinguished, said safety shutoff valve in the fuel supply line for the main burner being arranged so that when in closed position it shuts off the supply of fuel to both said main burner and to said stand-by pilot burner.

18. Apparatus according to claim 17 wherein there is additional shutoff means in the fuel supply line leading to the main burner and in the fuel supply line leading to said first pilot burner, which additional shutoff means is adapted to shut off the supply of fuel to both the main burner and the first pilot burner and is capable of being opened to reestablish a supply of fuel to the main burner and to the first pilot burner without ignition of said first pilot burner, the additional shutoff means in the fuel supply line leading to the main burner being disposed between the fuel outlet of the safety shutoff valve and the main burner.

ROBERT A. WITTMANN.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,971,704 Castonguay Aug. 28, 1934 2,063,834 Bast et al. Dec. 8, 1934 2,049,958 Jones et al. Aug. 4, 1936 2,063,834 Bast et a1 Dec. 8, 1936 2,072,034 Geurink et a1 Feb; 23, 1937 2,072,552 Gauger Mar. 2, 1937 2,087,433 Hollman 1 July 20, 1937 2,098,092 Matthews Nov. 2, 1937 2,164,887 Roberts et al July 4, 1939 2,233,659 Wittmann Mar. 4, 1941 2,299,155 Lange Oct. 20, 1942 2,359,921 Kliever Oct. 10, 1944 2,478,386 Gauger Aug. 9, 1949 2,483,191 Gauger Sept. 27, 1949 

